Jun-ichi Fukuda (Kyushu U): Simulation of structural relaxation and phase transition of liquid crystalline blue phases

Liquid crystalline blue phases are interesting examples of complex chiral structures of soft matter. Cubic blue phases, known as BPI and BPII, contain a regular array of topological line defects of orientational order (disclinations). We study the transformation dynamics of blue phases by numerically solving a Langevin-type equation for the orientational order parameter. The elusive task of identifying the complex local structures of blue phases is carried out with the aid of machine learning. We particluarly focus on the transformation from a perfect BPII lattice to BPI with twin boundaries, and clarify its dynamics.